U.S. patent number 4,479,685 [Application Number 06/505,660] was granted by the patent office on 1984-10-30 for flexible magnetic electrical connector and cable incorporating that connector.
This patent grant is currently assigned to Exxon Production Research Co.. Invention is credited to Robert A. Kirby.
United States Patent |
4,479,685 |
Kirby |
October 30, 1984 |
Flexible magnetic electrical connector and cable incorporating that
connector
Abstract
This invention is an electrical connector held together by
flexible magnetic substrates which also form the support for the
connector's electrical contacts. The connector has many uses but is
especially suitable for the connection between sections of
hydrophone streamer cables.
Inventors: |
Kirby; Robert A. (Houston,
TX) |
Assignee: |
Exxon Production Research Co.
(Houston, TX)
|
Family
ID: |
24011267 |
Appl.
No.: |
06/505,660 |
Filed: |
June 20, 1983 |
Current U.S.
Class: |
439/40; 367/153;
367/20; 439/271; 439/291; 439/451; 439/591; 439/625 |
Current CPC
Class: |
H01R
11/30 (20130101) |
Current International
Class: |
H01R
11/30 (20060101); H01R 11/11 (20060101); H01R
011/30 (); H01R 025/00 () |
Field of
Search: |
;339/12R,48,49B,94R,94M,151C,18R,184M,184R,104,59R,59M ;285/9M
;367/14,15,20,153,154,156,177 ;403/DIG.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: McGlynn; Joseph H.
Assistant Examiner: Bishop; Steven C.
Attorney, Agent or Firm: Wheelock; E. Thomas Bell; Keith
A.
Claims
I claim as my invention:
1. An electrical connector comprising:
at least two flexible, magnetic and substantially electrically
non-conductive substrates each having contact means mounted therein
with contact faces on a first side of each of said substrates and
adapted to meet in face to face contact when said substrates are
juxtaposed, each said contact means adapted to accept at least one
electrical wire on a second side of said substrates, and
indexing means adapted to permit said at least two substrates to be
juxtaposed in a predetermined position.
2. The connector of claim 1 wherein each of said substrate has
attached thereto a tab for separating said substrate from
juxtaposition with another.
3. The connector of claim 1 wherein said indexing means comprise
indexing pins and holes.
4. The connector of claim 1 wherein said substrate is comprised of
a thin rubbery material having magnetic particles dispersed
therein.
5. The connector of claim 4 wherein said magnetic particles are
dispersed in alternating rows of opposite magnetic orientation.
6. A watertight electrical connector assembly comprising:
a first and a second flexible, magnetic, and substantially
electrically non-conductive substrate, each having contact means
mounted therein with contact faces on a first side of each of said
substrates and adapted to meet in face to face contact when said
substrates are juxtaposed,
electrical wires connected to each said contact means on a second
side of each of said substrates, said wires from said first and
second substrates forming a first and second bundle
respectively,
said first and second bundles fixably attached in first and second
bulkheads, said bulkheads having sealing means disposed
thereabout,
boot means slidable over and extending from said first bulkhead to
said second bulkhead and sealing against said sealing means
disposed in said bulkheads, and
first and second split ring keepers adapted to maintain said boot
in sealing contact with said first and second bulkheads.
7. The connector assembly of claim 6 wherein each said substrate
has attached thereto a tab for separating each said substrate from
juxtaposition with another.
8. The connector assembly of claim 6 wherein said connector
assembly further comprises indexing means adapted to permit said
substrates to be juxtaposed in a predetermined position.
9. The connector assembly of claim 6 wherein said substrate is
comprised of a thin rubbery material having magnetic particles
dispersed therein.
10. The connector assembly of claim 9 wherein said magnetic
particles are dispersed in alternating rows of opposite magnetic
orientation.
11. The connector assembly of claim 6 wherein said sealing means
comprise "O" rings.
12. The connector assembly of claim 6 wherein said assembly
additionally comprises stress members extending at least from said
first bulkhead to said second bulkhead.
13. A hydrophone streamer cable section comprising:
a flexible hydrophone housing containing at least one hydrophone,
having two ends, and terminated by a bulkhead at each said end,
electrical connector means mounted on each said bulkhead, each said
connector means being comprised of a flexible, magnetic, and
substantially electrically non-conductive substrate having contact
means mounted therein with contact faces on a first side of said
substrate, said contact means adapted to accept an electrical wire
extending from said at least one hydrophone through a bulkhead to a
second side of said substrate, and having indexing means to permit
said connector means to be juxtaposed in a predetermined position
to a similar connector.
14. The cable of claim 13 wherein each said substrate has attached
thereto a tab for separating said substrate from juxtaposition with
another.
15. The cable of claim 13 wherein said indexing means comprise
indexing pins and holes.
16. The cable of claim 13 wherein said substrate is comprised of a
thin rubbery material having magnetic particles dispersed
therein.
17. The cable of claim 16 wherein said magnetic particles are
dispersed in alternating rows of opposite magnetic orientation.
18. The cable of claim 13 wherein stress members extend from
bulkhead to bulkhead and are fixedly attached thereto.
Description
OBJECT OF THE INVENTION
This invention is a flexible electrical connector comprising a
number of flexible magnets and contacts. The invention also
involves a cable using the connector. The cable is especially
suitable for use as a marine seismic cable.
BACKGROUND OF THE INVENTION
The exploration of offshore areas for oil and gas is performed
almost exclusively with boats towing one or more of a variety of
seismic sources and a large number of hydrophones near the surface
of the water. Generally, the seismic sources towed behind the boat
emit a sharp pulse which travels down through the water, through
the seafloor, into the subseafloor region, and reflects off the
interface between two geologic layers of differing densities. The
reflected pulse then retraces a similar course and is detected by
the hydrophones towed behind the seismic boat.
The hydrophones are typically included in a long streamer cable.
The cable may be made up of a number of sections, each filled with
oil for proper buoyance and containing a number of hydrophones.
Modern cables may be two miles or more in length and contain 4,000
hydrophones. A long cable with a great number of hydrophones
provides better resolution of the shape of subsurface geologic
features than does a shorter streamer with a smaller number of
geophones and often does so with less background noise.
As mentioned above, the cable may be made up of a large number of
sections. In this way, if the cable is damaged, e.g., by shark
bite, it can be pulled onto the boat until the damaged section is
brought aboard, the section unplugged, a new section installed and
the cable redeployed in the water. Repairs to the damaged cable may
be undertaken without substantial interruption of the exploration
activity.
One of the greatest sources of unreliability in a marine seismic
cable lies with the electrical connectors used to join adjacent
sections of cable. It is not uncommon that a cable will have ten
fifty-pin connectors at each of its ends. These connectors are
located in a boot which may be up to six feet in length. The
connectors typically have small delicate pins and sockets which are
subject to mismating. Mismating the two connector halves tends to
bend or break the small pins. The large number of mating pins
requires special tools to overcome the high friction resistance in
separating the halves. The boots may be rigid, in contrast to the
pliable nature of the section body, to protect the integrity of the
sockets. The junction between the pliable cable sections and the
rigid boots, therefore, is susceptible to separation or tearing.
The cables and connectors described in U.S. Pat. No. 4,204,188 to
Weichart et al, issued May 20, 1980, and U.S. Pat. No. 4,260,211 to
Mollere, issued Apr. 7, 1981, are typical of this design. A similar
device having a pivoted junction between cable sections is
disclosed in U.S. Pat. No. 3,350,678 to McLord, issued Oct. 31,
1967.
As noted above, an aspect of the instant invention is the use of
flexible magnetic substrate as part of a flexible electrical
connector having near-flush contacts imbedded therein.
Other connectors using flush contacts are known. See U.S. Pat. No.
2,234,982 to Ross, issued Mar. 18, 1941 and U.S. Pat. No. 3,080,544
to Statt et al, issued Mar. 5, 1963. U.S. Pat. No. 3,731,258 to
Spicer, issued May 1, 1973, discloses both flush contacts and a
flexible rubber substrate. None of Ross, Stratt et al, or Spicer,
however, disclose a flexible magnetic substrate.
SUMMARY OF THE INVENTION
This invention centers around a flexible magnetic electrical
connector having a wide variety of uses. The invention also
includes a cable incorporating the flexible electric magnetic
connector and a boot suitable for protecting the electrical
connector if it is used between cable sections.
The connector itself is made up of at least two mating portions
which are made up of flexible, nonconductive, magnetic substrate
portions. The flexible material of construction appears, to the
observer, to be a thin but dense section of rubber. The included
magnetic particles, in the material available commercially, are
alternately polarized in paths through the material. Each substrate
has a number of stubby contact surfaces slightly elevated from the
face of the substrate adapted to meet in face to face contact when
the substrates are assembled. The contact surfaces are placed on
the substrates in positions such that rows of opposite polarities
on the substrates are in contact when the connector is
assembled.
Index pins are installed in the substrate to ensure proper
alignment of contact surfaces.
The flexible magnetic substrates need not be merely mated in a
matching pattern of contact surfaces; the substrates may form the
junction point of, e.g., a wiring harness where a number of
different wiring sections meet at a common connector. In such a
case, a number of smaller substrates would connect to a single
large substrate.
It may be advantageous in some circumstances to plate the contact
surfaces with a material which is not susceptible to corrosion,
such as gold. Since the usual wiping action performed by a
male/female plug does not occur on the instant invention, other
methods of wiping, such as by twisting during assembly, may be
desirable.
One particularly suitable use for the invention connector disclosed
herein is as the connector between sections of marine seismic
cable. As was discussed above, connectors previously used in such
service have been hard to separate and prone to bent pins due to
mismating during assembly. Since the inventive connector has no
pins, these problems are obviated.
Also disclosed is a boot assembly especially suitable for use with
the magnetic connector which has an outer housing which can be slid
completely out of the area of the connector. In this way the
magnetic connector can be grasped with ease during disassembly.
A seismic cable adapted for using the boot assembly is a portion of
the inventive concept.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of a connector, without attached
wires, made according to the invention.
FIG. 1A shows a cutaway side view of a desirable variation of a
contact insert suitable for placement in the connector of FIG.
1.
FIG. 2 shows a partial cutaway side view of the junction between
two sections of seismic cable incorporating the inventive connector
and protective boot.
FIGS. 3A and 3B are top and bottom views of one of the split ring
keeper halves used on the boot shown in FIG. 2.
FIG. 3C is a end view of the assembled split ring keeper of FIGS.
3A and 3B .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
One configuration of the inventive electrical connector is shown in
FIG. 1. The connector depicted there is shown without attached
wires for the purpose of simplicity of explanation. The variation
shown in the figure is complex in that it utilizes four separate
flexible, magnetic substrates, i.e., first substrate 10, small
substrate 32, medium substrate 20, and large substrate 26. The
first substrate 10 has a number of index pins located therein. For
instance, pins 12 and 14 are embedded in substrate 10 and engage
matching index holes 16 and 18 in medium substrate 20. Similar
mating index pins 22 and index holes 24 are shown in conjunction
with large substrate 26. Similarly, pins 28 and index holes 30 are
shown in conjunction with the small substrate 32. Each of
substrates 20, 26, and 32 are shown to have a tab 34 attached to
facilitate easy removal from substrate 10.
Each of the substrates has mounted therein a number of inserts
which serve as contacts. These contacts are shown at 36 both in
FIG. 1 and, in cross section, in FIG. 1A. Insert 36 desirably has
contact face 38 and a wire receiving end 40. Contact face 38 may be
slightly rounded and extends slightly above the face of substrate
10. Wire receiving end 40 is shown to be a hollow cylinder which
may be used to accept one or more soldered wires. The wire
receiving end may also be of other known designs such as the spade
end, loop end, or screw receptacle. The contact face 38 need not be
rounded but may be of such shape as would provide a shallow
engagement. It is contemplated that the contact insert 36 or its
contact face 38 be plated with a corrosion resistant metal such as
gold if the atmosphere of use requires such an expedient. The
contact inserts may be of a ferromagnetic material such as iron so
as to enhance the magnetic attraction between the substrates and
the inserts. The inserts may be independently magnetic.
The substrates, such as 10, 20, 26, and 32, desirably are made of a
rubberized, magnetic, flexible material having the tradename
PLASTIFORM manufactured by the Minnesota Mining and Manufacturing
Company, but it is not necessary to do so. This proprietary
material typically comes with an alternating north-south
orientation of the the metallic magnetic particles in the
surrounding polymeric matrix. This alternating orientation is
depicted by the north-south symbols at the ends of substrate 10 and
substrate 32 in FIG. 1. If this material is chosen for use, it is
necessary that the constructor of the inventive connector position
the index pins, for instance, 12 and 14, and index holes, 16 and
18, and the various contact inserts 36 within particular substrates
so that, when two substrates are indexed and in contact, the south
orientations in one substrate are adjacent the north orientations
in the other substrate. Such a configuration is shown in FIG. 1. It
should be apparent from the drawing that the various inserts 36 are
placed within opposite substrates so that two contact faces 38 are
in contact.
It is not necessary that there be a one to one conformance between
the number of contact inserts in adjacent substrates. It is
contemplated that, for instance, should it be found necessary to
direct a number of wire leads to a single circuit point such as an
electrical ground, a single substrate with a number of contact
inserts may be placed directly onto a single conductive
substrate.
As mentioned above, there is no wiping action in this connector
tending to keep the contacts clean. Consequently, in some services
it may be necessary to modify the index pins so that during
assembly one substrate of the connector is twisted in relation to
the other to perform wiping movement between a number of contact
faces 38.
Similarly, although indexing pins and matching indexing holes are
the preferred method of assuring a match between appropriate
contact inserts on adjacent substrates, other indexing means are of
course contemplated. For instance, the edge of adjacent substrates
may be fitted into slots on a receptacle mounted in a particular
location as in the fire wall of an automobile or airplane. A single
indexing device having a shape which may be oriented at only one
direction with respect to a mating portion may be installed on a
substrate. A wall may be built up on one substrate which may match
the outside shape of one or more mating substrates, much in a way a
child's puzzle fits together.
FIG. 2 shows one desirable use for the inventive connector
described with regard to FIG. 1. The two substrates 42 and 44 are
held in relative proximity by the magnetic forces discussed above.
They are not in complete contact since each of the substrate
desirably has contact faces (not shown) holding the two substrates
slightly apart. Each of the contacts is connected to a wire, for
instance 46 and 48. The accumulation of wires is bundled from each
substrate 42, 44 to make a cable 50 and 52 respectively. In this
variation, each substrate, wire, and cable, is a portion of an
attached geophone section, shown generally as 54 and 56. For the
purposes of illustration, speaking of the section 54 on the right
end of FIG. 2, cable 50 passes through cable bulkhead 58 and onto
hydrophones located farther down the section. The hydrophones form
no portion of this invention, are well known in the art, and are
therefore not described in any great detail. The wire bundle 50 is
embedded in cable bulkhead 58. No liquid passes through bulkhead
58. Cable bulkhead 58 also has one or more stress members 60
embedded therein. The stress members are made up of strong
stress-carrying materials such as wire rope and should be easily
disconnected at connection 62. The stress members 60 pass all the
way through the hydrophone section, e.g., 54, to its other end
where they may make similar connections with the next hydrophone
cable section. The outside of cable bulkhead 58 carries a sealing
means 64, such as an O-ring, or other suitable seal design. The
outside of cable bulkhead 58 is of such a size that is slips
readily inside boot assembly 66 and yet is snug against its inside
through the sealing means 64. Cable bulkhead 58 is also firmly
attached to the pliable skin 68 of the hydrophone section. The
relationship between cable bulkhead 58 and boot assembly 66 is
maintained by a split ring keeper 70 made up of two identical
halves 72 as shown in FIGS. 3A, 3B, and 3C. FIG. 3A shows an inside
view of the split ring keeper half 72. As can be seen, it has a
small circumferential slot 74 designed to take the mating portion
of cable bulkhead 58. It has a larger circumferential slot 76 to
engage the mating portion of boot assembly 66. There are holes 78
for inserting screws or other means to join the two split ring
keeper halves together over the juncture of boot assembly 66 and a
cable bulkhead forming the end of a hydrophone cable section. FIG.
3C shows, from an end view, how the two halves are joined.
The method of disassembling and assembling boot assembly and
inventive flexible electric cable should be apparent from the prior
description. However, the joining means in holes 78 are removed
from each of the split ring keepers 72 found at the end of boot
assembly 66. The split ring keepers are removed from each end of
boot assembly 66. Boot assembly 66 is then slid over cable bulkhead
58 thereby exposing stress members 60 and the connector. Stress
members 60 are disconnected at stress member connections 62 and
finally substrates 42 and 44 are pulled apart. Assembly is
performed in the reverse order.
The present invention has been described and illustrated by means
of specific embodiments, it is to be understood that numerous
changes and modifications may be made therein without departing
from the spirit and scope of the invention as defined in the
following claims.
* * * * *